Summary
MantisBT: Remote Code Execution via eval() Class Hoisting in admconfigset.php
MantisBT 2.28.3 and earlier contains a remote code execution vulnerability in the admin "Manage Configuration" feature (adm_config_set.php). When setting a configuration value with a non-string type (integer, float, complex), the value is passed through ConfigParser -> Tokenizer, which calls eval() with a return; prefix intended to prevent code execution.
However, PHP hoists function and class declarations at compile time, even past a return statement. An attacker can define a class in the eval()'d code that hijacks a class loaded later via PHP's autoloader, achieving arbitrary code execution.
This vulnerability requires administrator access to the web UI (adm_config_set.php). The REST API's ConfigsSetCommand does NOT use Tokenizer/eval() and is not affected.
Workarounds
None.
Resources
Credits
McCaulay Hudson (@_McCaulay) of watchTowr
Impact
- Remote code execution as the web server user (www-data) from an authenticated administrator session
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Frequently Asked Questions
- What is CVE-2026-49273? CVE-2026-49273 is a high-severity security vulnerability in mantisbt/mantisbt (composer), affecting versions >= 1.3.0, <= 2.28.3. It is fixed in 2.28.4.
- Which versions of mantisbt/mantisbt are affected by CVE-2026-49273? mantisbt/mantisbt (composer) versions >= 1.3.0, <= 2.28.3 is affected.
- Is there a fix for CVE-2026-49273? Yes. CVE-2026-49273 is fixed in 2.28.4. Upgrade to this version or later.
- Is CVE-2026-49273 exploitable, and should I be worried? Whether CVE-2026-49273 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-49273 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-49273? Upgrade
mantisbt/mantisbtto 2.28.4 or later.